1bs4: Difference between revisions

Eubacterial proteins are synthesized with a formyl group at the N-terminus, which is hydrolytically removed from the nascent chain by the mononuclear, iron enzyme peptide deformylase. Catalytic efficiency strongly depends on, the identity of the bound metal. We have determined by X-ray, crystallography the Fe2+, Ni2+ and Zn2+ forms of the Escherichia coli, enzyme and a structure in complex with the reaction product Met-Ala-Ser., The structure of the complex, with the tripeptide bound at the active, site, suggests detailed models for the mechanism of substrate recognition, and catalysis. Differences of the protein structures due to the identity, of the bound metal are extremely small and account only for the, observation that Zn2+ binds more tightly than Fe2+ or Ni2+. The striking, loss of catalytic activity of the Zn2+ form could be caused by its, reluctance to change between tetrahedral and five-fold metal coordination, believed to occur during catalysis. N-terminal formylation and subsequent, deformylation

1BS4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with SO4, ZN and 2PE as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Formylmethionine_deformylase Formylmethionine deformylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.31 3.5.1.31] Structure known Active Sites: ZNA, ZNB and ZNC. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1BS4 OCA].  

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